*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
/*    字体无法选中*/
    user-select: none;
}
body{
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 12px;
    background-color: #ecf0f3;
    color: #a0a5a8;
}
.shell{
    position: relative;
    width: 1000px;
    min-width: 1000px;
    min-height: 600px;
    height: 600px;
    padding: 25px;
    background-color: #ecf0f3;
    box-shadow: 10px 10px 10px #d1d9e6, -10px -10px 10px #f9f9f9;
    border-radius: 12px;
    overflow: hidden;
}
/*设置响应式*/
@media (max-width: 1200px){
    .shell{
        transform: scale(0.7);
    }
}
@media (max-width: 1000px){
    .shell{
        transform: scale(0.6);
    }
}
@media (max-width: 800px){
    .shell{
        transform: scale(0.5);
    }
}
@media (max-width: 600px){
    .shell{
        transform: scale(0.4);
    }
}
.container{
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    top: 0;
    width: 600px;
    height: 100%;
    padding: 25px;
    background-color: #ecf0f3;
    transition: 1.25s;
}
.form{
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    width: 100%;
    height: 100%;
}
.iconfont{
    margin: 0 5px;
    border: rgba(0,0,0,0.5) 2px solid;
    border-radius: 50%;
    font-size: 25px;
    padding: 3px;
    opacity: 0.5;
    transition: 0.1s;
}
.iconfont:hover{
    opacity: 1;
    transition: 0.15s;
    cursor: pointer;
}
.form_input{
    width: 350px;
    height: 40px;
    margin: 4px 0;
    padding-left: 25px;
    font-size: 13px;
    letter-spacing: 0.15px;
    border: none;
    outline: none;
    background-color: #ecf0f3;
    transition: 0.25s ease;
    border-radius: 8px;
    box-shadow: inset 2px 2px 4px #d1d9e6,inset -2px -2px 4px #f9f9f9;
}
.form_input:focus{
    box-shadow: inset 4px 4px 4px #d1d9e6,inset -4px -4px 4px #f9f9f9;
}
.form_span{
    margin-top: 30px;
    margin-bottom: 12px;
}
.form_link{
    color: #181818;
    font-size: 15px;
    margin-top: 25px;
    border-bottom: 1px solid #a0a5a8;
    line-height: 2;
}
.title{
    font-size: 34px;
    font-weight: 700;
    line-height: 3;
    color: #181818;
    letter-spacing: 10px;
}
.description{
    font-size: 14px;
    letter-spacing: 0.25px;
    text-align: center;
    line-height: 1.6;
}
.button{
    width: 180px;
    height: 50px;
    border-radius: 25px;
    margin-top: 50px;
    font-weight: 700;
    font-size: 14px;
    letter-spacing: 1.15px;
    background-color: #4b70e2;
    color: #f9f9f9;
    box-shadow: 8px 8px 16px #d1d9e6,-8px -8px 16px #f9f9f9;
    border: none;
    outline: none;
}
.a-container{
    z-index: 100;
    left: calc(100% - 600px)
}
.b-container{
    left: calc(100% - 600px);
    z-index: 0;
}
.switch{
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 400px;
    padding: 50px;
    z-index: 200;
    transition: 1.25s;
    background-color: #ecf0f3;
    overflow: hidden;
    box-shadow: 4px 4px 4px #d1d9e6,-4px -4px 10px #d1d9e6;
}
.switch_circle{
    position: absolute;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    background-color: #ecf0f3;
    box-shadow: inset 8px 8px 12px #b8bec7,inset -8px -8px 12px #fff;
    bottom: -60%;
    left: -60%;
    transition: 1.25s;
}
.switch_circle-t{
    top: -30%;
    left: 60%;
    width: 300px;
    height: 300px;
}
.switch_container{
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    position: absolute;
    width: 400px;
    padding: 50px 55px;
    transition: 1.25s;
}
.switch_button{
    cursor: pointer;
}
.switch_button:hover,
.submit:hover{
    box-shadow: 6px 6px 10px #d1d9e6,-6px -6px 10px #f9f9f9;
    transform: scale(0.985);
    transition: 0.25s;
}
.switch_button:active,
.switch_button:focus{
    box-shadow: 2px 2px 6px #d1d9e6,-2px -2px 6px #f9f9f9;
    transform: scale(0.97);
    transition: 0.25s;
}
.is-txr{
    left: calc(100% - 400px);
    transition: 1.25s;
    transform-origin: left;
}
.is-txl{
    left: 0;
    transition: 1.25s;
    transform-origin: right;
}
.is-z{
    z-index: 200;
    transition: 1.25s;
}
.is-hidden{
    visibility: hidden;
    opacity: 0;
    position: absolute;
    transition: 1.25s;
}
.is-gx{
    animation: is-gx 1.25s;
}
@keyframes is-gx {
    0%,
    10%,
    100%{
        width: 400px;
    }
    30%,
    50%{
        width: 500px;
    }
}